Within the onMount example function above we have access to both Express applications, the one being mounted this and the instanced being mounted to this.parent. There is also this.mountpath which can be used to detect the path (in our example `/someRoute') that was used to mount our child middleware.

Manipulating The Parent

This makes it possible for us to add a route to the parent or perhaps evaluate the routes on the parent by analyzing this.parent._stack as well as get access to all other functions of the parent app.